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Discussion Starter #164
oh thats right.
20 miles driven yesterday. Yes I am still running the heater core in reverse, and it's still running much warmer than I'd like. About 230, reaching 240 at one point. Doesn't seem to be getting to go hotter but it's not far from that magic 260 overheating number. Not sure where to go now. I guess it's a heater core for me.

In other news, failed inspection but only for a few lights. The previous owner had removed the bulbs and let the wires dangle for the front side marker lights so I thought they were just reflectors. Found the wires and fixed it. One side tag light was out. And the little city bulbs were also missing. Should be good for reinspection tomorrow.
 

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I forget if yours is a B5.5, but if so, do you know the front side marker lights come out from the front, with no tools?
You press on one side, against a spring, then slide the whole light 3/16" to let the retainer tab on the other end pop out. Then the whole light comes out; lamp socket unplugs from the back.
 

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Discussion Starter #166
I forget if yours is a B5.5, but if so, do you know the front side marker lights come out from the front, with no tools?
You press on one side, against a spring, then slide the whole light 3/16" to let the retainer tab on the other end pop out. Then the whole light comes out; lamp socket unplugs from the back.
Yeah that's how it worked, but on one side they pulled the socket out and just let it drop back into the engine bay. The other side broke the socket mount and needs to be replaced. I had to fish out both sockets from underneath the car to find them. I'll stop by a junkyard tomorrow to find The replacement. I'll have to snip and splice in a good socket from the donor car.
 

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191F at the vent? I think that might be warm enough.
 

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Can not remember what your reading was before at the vent , 165?, regardless the heater vent should be reading real close to the coolant temp coming out of the engine since that (heater core) is directly after the engine from a circulation standpoint, if in fact the air going into the heater core does not have a huge differential and being recirculated. How did the lower coolant hose feel?.....Also keep in mind the oil cooler might be in the same compromised status as was the heater core, its flow also feeds the suction side of the water pump.
 

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Discussion Starter #171
It was reading about 130 before. And we shall see eater today. I think the oil cooler is ok but I have a spare on hand just in case. Just trying to avoid draining my coolant AGAIN.
 

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2004 B5.5 Variant 1.8T
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It was reading about 130 before. And we shall see eater today. I think the oil cooler is ok but I have a spare on hand just in case. Just trying to avoid draining my coolant AGAIN.
At least with the oil cooler, you can just clamp the lines to it and remove them. No need to drain coolant to replace it.
 

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Discussion Starter #173
16 miles in variable conditions and speeds, did not rise above 208F. I'll be taking an even longer drive later but I think we're good.

Now, for anyone that suggests that a clogged heater core can't cause overheating, stop saying that. It apparently can!
 

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Discussion Starter #174
16 miles in variable conditions and speeds, did not rise above 208F. I'll be taking an even longer drive later but I think we're good.

Now, for anyone that suggests that a clogged heater core can't cause overheating, stop saying that. It apparently can!
I spoke too soon. I did another 10 miles with no issues. Then when I went to drive home a couple hours later it was right back to overheating. I am fairly certain the thermostat was not opening again. I am getting so fed up with this thing I don't even know where to go from here.

I am going to try to drain and vacuum bleed the system properly, since I may not have gotten it right before. I didn't have my air compressor and I do now. I'll report back. Also considering running without a thermostat to see how it does.

I don't know. I'm kinda fed-up.
 

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If you have an air compressor then I suggest pressure test the coolant system to 20psi (cap vent will open at that pressure or a little above so I assume that's the max pressure). I recall you said it holds vacuum or something but see what it's actually holding. The only other thing I can think of is the fan, its speed is determined by viscuous clutch which is supposed to be determined by temperature, I think, but I believe that was covered as well earlier in the thread.
 

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Discussion Starter #176
The fan clutch is new. That did help a little bit when I did it. I did use my air compressor to pressure test the cooling system. It did hold the pressure that I gave it.
 
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